Message-ID: <11d3c806-04b6-da54-65f1-c0bd154affbc@linaro.org>
Date:   Thu, 2 Mar 2023 09:28:21 +0100
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Subject: Re: [RFC PATCH 07/16] dt-bindings: pinctrl: ralink: add new
 compatible strings
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To:     =?UTF-8?B?QXLEsW7DpyDDnE5BTA==?= <arinc.unal@arinc9.com>,
        Rob Herring <robh@kernel.org>
Cc:     Sergio Paracuellos <sergio.paracuellos@gmail.com>,
        Linus Walleij <linus.walleij@linaro.org>,
        Krzysztof Kozlowski <krzysztof.kozlowski+dt@linaro.org>,
        linux-mediatek@lists.infradead.org, linux-mips@vger.kernel.org,
        linux-gpio@vger.kernel.org, devicetree@vger.kernel.org,
        linux-arm-kernel@lists.infradead.org, linux-kernel@vger.kernel.org,
        Matthias Brugger <matthias.bgg@gmail.com>,
        Sean Wang <sean.wang@kernel.org>,
        William Dean <williamsukatube@gmail.com>,
        Daniel Golle <daniel@makrotopia.org>,
        Daniel Santos <daniel.santos@pobox.com>,
        Luiz Angelo Daros de Luca <luizluca@gmail.com>,
        Frank Wunderlich <frank-w@public-files.de>,
        Landen Chao <Landen.Chao@mediatek.com>,
        DENG Qingfang <dqfext@gmail.com>,
        Sean Wang <sean.wang@mediatek.com>, erkin.bozoglu@xeront.com
References: <20230222183932.33267-1-arinc.unal@arinc9.com>
 <20230222183932.33267-8-arinc.unal@arinc9.com>
 <20230227173333.GA496999-robh@kernel.org>
 <d7aea90f-d077-3a41-996c-804c95d72e24@arinc9.com>
 <20230301024431.GA251215-robh@kernel.org>
 <ae3346de-140f-f181-b6a3-ccaa694e1548@arinc9.com>
From:   Krzysztof Kozlowski <krzysztof.kozlowski@linaro.org>
In-Reply-To: <ae3346de-140f-f181-b6a3-ccaa694e1548@arinc9.com>
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Precedence: bulk

On 01/03/2023 09:15, Arınç ÜNAL wrote:
> On 1.03.2023 05:44, Rob Herring wrote:
>> On Tue, Feb 28, 2023 at 07:46:36PM +0300, Arınç ÜNAL wrote:
>>> On 27/02/2023 20:33, Rob Herring wrote:
>>>> On Wed, Feb 22, 2023 at 09:39:23PM +0300, arinc9.unal@gmail.com wrote:
>>>>> From: Arınç ÜNAL <arinc.unal@arinc9.com>
>>>>>
>>>>> Add the ralink,rt2880-pinmux compatible string. It had been removed from
>>>>> the driver which broke the ABI.
>>>>>
>>>>> Add the mediatek compatible strings. Change the compatible string on the
>>>>> examples with the mediatek compatible strings.
>>>>>
>>>>> Signed-off-by: Arınç ÜNAL <arinc.unal@arinc9.com>
>>>>> ---
>>>>>    .../devicetree/bindings/pinctrl/ralink,mt7620-pinctrl.yaml | 7 +++++--
>>>>>    .../devicetree/bindings/pinctrl/ralink,mt7621-pinctrl.yaml | 7 +++++--
>>>>>    .../devicetree/bindings/pinctrl/ralink,rt2880-pinctrl.yaml | 7 +++++--
>>>>>    .../devicetree/bindings/pinctrl/ralink,rt305x-pinctrl.yaml | 7 +++++--
>>>>>    .../devicetree/bindings/pinctrl/ralink,rt3883-pinctrl.yaml | 7 +++++--
>>>>>    5 files changed, 25 insertions(+), 10 deletions(-)
>>>>>
>>>>> diff --git a/Documentation/devicetree/bindings/pinctrl/ralink,mt7620-pinctrl.yaml b/Documentation/devicetree/bindings/pinctrl/ralink,mt7620-pinctrl.yaml
>>>>> index 1e63ea34146a..531b5f616c3d 100644
>>>>> --- a/Documentation/devicetree/bindings/pinctrl/ralink,mt7620-pinctrl.yaml
>>>>> +++ b/Documentation/devicetree/bindings/pinctrl/ralink,mt7620-pinctrl.yaml
>>>>> @@ -17,7 +17,10 @@ description:
>>>>>    properties:
>>>>>      compatible:
>>>>> -    const: ralink,mt7620-pinctrl
>>>>> +    enum:
>>>>> +      - mediatek,mt7620-pinctrl
>>>>> +      - ralink,mt7620-pinctrl
>>>>
>>>> We don't update compatible strings based on acquistions nor marketing
>>>> whims. If you want to use 'mediatek' for new things, then fine.
>>>
>>> Understood. Only the SoCs with rtXXXX were rebranded, the mtXXXX SoCs share
>>> the same architecture from Ralink, so they were incorrectly called Ralink
>>> SoCs.
>>>
>>> I can remove the new strings from Ralink SoCs and add them only for MediaTek
>>> SoCs. Or you could make an exception for this one, regarding the situation.
>>> Whatever you think is best.
>>
>> I'm not in a position to make an exception as I know little about this
>> platform. Carrying both strings is a NAK. Either you (and everyone using
>> these platforms) care about the ABI and are stuck with the "wrong"
>> string. In the end, they are just unique identifiers. Or you don't care
>> and break the ABI and rename everything. If you do that, do just that in
>> your patches and make it crystal clear in the commit msg that is your
>> intention and why that is okay.
> 
> Ralink had their MIPS SoCs pre-acquisition, RT2880, etc. MediaTek 
> introduced new SoCs post-acquisition, MT7620, MT7621, MT7628, and 
> MT7688, utilising the same platform from Ralink, sharing the same 
> architecture code, pinctrl core driver, etc.
> 
> I don't intend to break the ABI at all. On the contrary, I fix it where 
> possible.
> 
> If I understand correctly, from this conversation and what Krzysztof 
> said, all strings must be kept on the schemas so I can do what I said on 
> the composed mail. Only match the pin muxing information on the strings 
> that won't match multiple pin muxing information from other schemas.
> 
> This way we don't break the ABI, introduce new compatible strings while 
> keeping the remaining ones, and make schemas match correctly.
> 
> Let me know if this is acceptable to you.

If by "introduce new compatible strings" you mean duplicate compatibles
to fix the ralink->mediatek, then you ignored entire email from Rob -
this and previous. We don't do this. Leave them as is.

If you meant something else, explain more...

Best regards,
Krzysztof